In general, a high voltage driving circuit is used for flat display panel (FDP) devices such as plasma display panel PDP devices, an Electro Luminescence Display (ELD), a Vacumm Fluorescent Display (VFD) or Field Emission Display (FED).
Such a high voltage driving circuit serves to drive a load by converting a signal having a logic level of 5 volts to a high signal more than tens of volts. A core skill in a high voltage driving circuit is to improve operating speed and to minimize power consumption. A number of high voltage driving circuits are required in the color display devices and therefore, even though a static current or a transient current flowing through any output terminal is small, an overall current and power dissipating at a display device become very large, resulting in an increase in power consumption.
As one conventional method for decreasing the power consumption in a high voltage circuit, there has been used a method for decreasing a static current. FIG. 1 shows an representative high voltage driving circuit according to the prior art, and FIG. 2 shows input/output waveforms which represent an output voltage Vout, a transient current IT flowing through an output transistor and a load current IL. This conventional high voltage driving circuit comprises a level shift circuit 1 for converting an input voltage Vin having a logic level to a high level of voltage and a complementary output circuit 2 for driving a load. The level shift circuit 1 comprises a latch circuit formed by P-channel transistors M1 and M3 and N-channel transistors M2 and M4, and prevents a possible flow of the static current during a time duration that a signal maintains a high state or low state. However, transistors M5 and M6 of the complementary output circuit 2 have a little rising and falling time during switching, so that there exists a time duration that transistors M5 and M6 of the complementary output circuit 2 have a little rising and falling time during switching, so that there exists a time a duration that transistors M5 and M6 are turned on simultaneously. Accordingly, during this time, and transient current IT flows as shown in FIG. 2. Likewise, even though the transient current is small compared to that of the complementary output circuit 2, it flows through transistors M1 and M2 which are connected in series between power source terminal VDDH and a ground terminal GND, and also flows through transistors M3 and M4 in the level shift circuit 1. As a result, even though the high voltage driving circuit in FIG. 1 can exclude the static current, it has a disadvantage that causes unnecessary power consumption because of a transient current which occurred during switching.